It's most definitely a site for readers, enabling you to organize and catalogue your books and to give and receive recommendations. The site has menu items for your Home page, your Profile, your Books, Groups, a Forum, and the ability to localize your book-finding habits - enter your address and the site will find local bookshops for you very quickly and very effectively.
One of its biggest advantages is that the site is much easier to understand and follow than Goodreads. It's more clearly laid out and is less confusing for newbies. Also, if you happen to be a writer with books to publicize, you can become a LibraryThing author and give away your books in order to receive reviews. There's a lot to explore here and for readers it can be an engrossing experience.
The LibraryThing home page is Here.